#!/usr/bin/env perl

#  Copyright (C) 2011 DeNA Co.,Ltd.
#
#  This program is free software; you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation; either version 2 of the License, or
#  (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#   along with this program; if not, write to the Free Software
#  Foundation, Inc.,
#  51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

use strict;
use warnings FATAL => 'all';

use English qw(-no_match_vars);
use Getopt::Long;
use Pod::Usage;
use MHA::ManagerConst;

my @monitoring_servers;
my ( $help, $version, $ssh_user, $ssh_port, $ssh_options, $master_host,
  $master_ip, $master_port );
my $timeout = 5;

$| = 1;
GetOptions(
  'help'             => \$help,
  'version'          => \$version,
  'secondary_host=s' => \@monitoring_servers,
  'user=s'           => \$ssh_user,
  'port=s'           => \$ssh_port,
  'options=s'        => \$ssh_options,
  'master_host=s'    => \$master_host,
  'master_ip=s'      => \$master_ip,
  'master_port=i'    => \$master_port,
  'timeout=i'        => \$timeout,
);

if ($version) {
  print "masterha_secondary_check version $MHA::ManagerConst::VERSION.\n";
  exit 0;
}

if ($help) {
  pod2usage(0);
}

unless ($master_host) {
  pod2usage(1);
}

sub exit_by_signal {
  exit 1;
}
local $SIG{INT} = $SIG{HUP} = $SIG{QUIT} = $SIG{TERM} = \&exit_by_signal;

$ssh_user    = "root" unless ($ssh_user);
$ssh_port    = 22     unless ($ssh_port);
$master_port = 3306   unless ($master_port);

if ($ssh_options) {
  $MHA::ManagerConst::SSH_OPT_CHECK = $ssh_options;
}
$MHA::ManagerConst::SSH_OPT_CHECK =~ s/VAR_CONNECT_TIMEOUT/$timeout/;

# 0: master is not reachable from all monotoring servers
# 1: unknown errors
# 2: at least one of monitoring servers is not reachable from this script
# 3: master is reachable from at least one of monitoring servers
my $exit_code = 0;

foreach my $monitoring_server (@monitoring_servers) {
  my $ssh_user_host = $ssh_user . '@' . $monitoring_server;
  my $command =
"ssh $MHA::ManagerConst::SSH_OPT_CHECK -p $ssh_port $ssh_user_host \"perl -e "
    . "\\\"use IO::Socket::INET; my \\\\\\\$sock = IO::Socket::INET->new"
    . "(PeerAddr => \\\\\\\"$master_host\\\\\\\", PeerPort=> $master_port, "
    . "Proto =>'tcp', Timeout => $timeout); if(\\\\\\\$sock) { close(\\\\\\\$sock); "
    . "exit 3; } exit 0;\\\" \"";
  my $ret = system($command);
  $ret = $ret >> 8;
  if ( $ret == 0 ) {
    print
"Monitoring server $monitoring_server is reachable, Master is not reachable from $monitoring_server. OK.\n";
    next;
  }
  if ( $ret == 3 ) {
    print "Master is reachable from $monitoring_server!\n";
    $exit_code = 3;
    last;
  }
  else {
    print "Monitoring server $monitoring_server is NOT reachable!\n";
    $exit_code = 2;
    last;
  }
}

exit $exit_code;

# ############################################################################
# Documentation
# ############################################################################

=pod

=head1 NAME

masterha_secondary_check - Checking master availability from additional network routes

=head1 SYNOPSIS

masterha_secondary_check -s secondary_host1 -s secondary_host2 .. --user=ssh_username --master_host=host --master_ip=ip --master_port=port

See online reference (http://code.google.com/p/mysql-master-ha/wiki/Parameters#secondary_check_script) for details.

=head1 DESCRIPTION

See online reference (http://code.google.com/p/mysql-master-ha/wiki/Parameters#secondary_check_script) for details.


